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741.
Relation between Electric Spark Sensitivity and Impact Sensitivity of Nitroaromatic Energetic Compounds 下载免费PDF全文
Impact and electric spark sensitivities of energetic compounds are two important sensitivity parameters, which are closely related to many accidents in working places. In contrast to electric spark sensitivity, impact sensitivity can be easily measured. A new simple method is introduced to correlate electric spark and impact sensitivities of nitroaromatic compounds. Two correcting functions are used to consider several molecular moieties for reliable prediction of electric spark sensitivity through the measured or estimated impact sensitivity of nitroaromatics. The model is optimized using a set of 28 CHNO polynitroaromatic explosives and then it is tested for some nitroaromatics containing the other atoms such as sulfur. The predicted electric sensitivities of the new method are also compared with the reported results of a new quantum mechanical approach. For 22 CHNO nitroaromatics, quantum mechanical calculations are within ±3.0 J of 18 measured values and more than ±3.0 J for remaining 4 experimental data. Meanwhile, the predicted results of the method are less than ±3.0 J for 28 CHNO nitroaromatics. The root‐mean‐square (rms) deviations of the new model and quantum mechanical are also 1.55 and 2.51 J, respectively. 相似文献
742.
Synthesis,Characterization, and Docking Evaluations of New Derivatives of Pyrimido[4,5‐c]pyridazine as Potential Human AKT1 Inhibitors 下载免费PDF全文
Ayla Hazrathoseyni Seyed Mohammad Seyedi Hossein Eshghi Ali Shiri Mohammad Saadatmandzadeh Ali Reza Berenji 《Journal of heterocyclic chemistry》2016,53(1):135-143
A number of new derivatives of pyrimido[4,5‐c]pyridazine have been synthesized from the treatment of 6‐acetyl‐3‐amino‐2,5‐diphenyl‐2,5‐dihydropyridazine‐4‐carbonitrile ( 1 ) as precursor with various reactants obtained quantitatively the desired products ( 2 ), ( 5 ), ( 7 ), and ( 9a , 9b , 9c , 9d , 9e ). The structures of all the synthesized products have been elucidated thoroughly. The potential AKT1 inhibitory activities of these new synthesized compounds have also been studied by docking calculations, which have been performed in Gold 5.2 software using Genetic algorithm. 相似文献
743.
Mohammad Hossein Keshavarz Mehran Hayati Sara Ghariban‐Lavasani Narges Zohari 《无机化学与普通化学杂志》2016,642(2):182-188
The knowledge of sensitiveness of an energetic compound to friction stimuli is important to ensure the safety of people and protection of property during shipment. The information on sensitivity to friction is considered very valuable for nitramines, which show relatively higher sensitivity with respect to the other classes of secondary explosives. This study presents a novel general simple model for prediction of the relationship between friction sensitivity and activation energy of thermolysis of cyclic and acyclic nitramines on the basis of their molecular structures. This methodology assumes that friction sensitivity of an energetic compound with general formula CaHbNcOd can be expressed as a function of activation energy of thermolysis and the contribution of specific molecular structural parameters. For 21 nitramines with different molecular structures, the new correlation has the root mean square and the average standard deviations of 14.2 and 17.8 N, respectively, as compared to experimental values. The proposed new method is also tested for further 8 nitramines containing complex molecular structures, which gives good predictions. 相似文献
744.
Mohammad Ali Karimi Mohammed Hadi Ghasemi Mohammad Javad Aghagoli Mostafa Hossein Beyki 《Mikrochimica acta》2016,183(11):2949-2955
Melamine functionalized cellulose@carbon nanotubes were prepared by the following method: (a) Cellulose was dissolved in a mixture of urea and NaOH solutions and then mixed with multiwall carbon nanotubes; (b) the MWCT-modified cellulose was precipitated by addition of water; (c) the MWCNTs were activated with thionyl chloride, and finally reacted with melamine. The resulting sorbent was used in preconcentration of Co(II) ions prior to their determination by flame atomic absorption spectroscopy. The sorbent was characterized by FTIR and field emission scanning electron microscopy. The effects of the pH value of the medium, contact time, and elution conditions were optimized. The calibration plot is linear in the 3 to 200 μg·L ̄1 Co(II) concentration range, the limit of detection is 0.8 μg·L ̄1, and the relative standard deviation (at a concentration of 100 μg·L ̄1) is 3.5 %. The maximum sorption capacity is 167 mg·g ̄1. The method was applied to the preconcentration of cobalt ions from (spiked) food and water samples and gave recoveries between 96 and 102 %. 相似文献
745.
A composite consisting of carbon nanotubes (CNT) and copper nanoparticles (CuNPs) was prepared by a chemical reduction method, and its structure characterized by scanning electron microscopy, transmission electron microscopy energy dispersive spectroscopy and FT-IR spectrometry. The hybrid composite was deposited on the surface of a disposable gold electrode that was manufactured from a commercial digital versatile gold disc by a drop casting method. The electrochemical properties of the modified electrode were investigated by cyclic voltammetry and differential pulse voltammetry. The sensor showed an excellent electrocatalytic activity towards oxidation of paracetamol (PA). The calibration plot (with current typically measured at 0.41 V vs. Ag/AgCl) is linear in the 0.5 to 80 μM concentration range, and the detection limit is as low as 10 nM. The sensor was successfully applied to the determination of PA in spiked water and tablet samples where it gave recoveries ranging between 95.25 and 100.5 %. 相似文献
746.
Mir Reza Majidi Mohammad Hossein Pournaghi-Azar Reza Fadakar Bajeh Baj Abdolhossein Naseri 《International journal of environmental analytical chemistry》2016,96(1):50-67
A novel ionic liquid, 1-(ferrocenyl butyl)-3-methylimidazolium tetrafluoroborate (Fc-IL), was synthesised. The nanocomposite of Fc-IL and multi-walled carbon nanotubes (MWCNTs) was constructed and used for surface modification of carbon-ceramic electrode. The modified electrode was applied to the determination of hydrazine. Operational parameters such as pH of the solution, ionic liquid volume and amount of carbon nanotubes, which affect the analytical performance of the modified electrode, were optimised. The linear range of the modified electrode toward hydrazine concentration was 0.96–106.10 μg L–1 with a detection limit of 0.64 μg L–1 (S/N = 3). The modified electrode displayed high repeatability, reproducibility, long-term life time and low response time (<3 s). The applicability of this method was further tested by analysing the hydrazine content in boiler-feed water samples containing different concentrations of hydrazine and the results were in good agreement with the spectrophotometry method. 相似文献
747.
Mostafa Khoshsefat Narges Beheshti Gholam Hossein Zohuri Saeid Ahmadjo Somaye Soleimanzadegan 《Polymer Science Series B》2016,58(5):487-494
The Late transition metal catalysts based on Ni(II) and Co(II) were synthesized and their structure and activity in polymerization of ethylene were compared. Methylaluminoxane (MAO) was used as a co-catalyst. To discover the optimum polymerization conditions, the effect of polymerization temperature, monomer pressure, [Al]: [Ni] molar ratio and time of polymerization were studied. Activity of the catalysts was promoted by increasing of the monomer pressure. The viscosity average molecular weights Mv of the synthesized polymers using 1,2-bis(2,4,6-trimethyl phenyl imino) acenaphthene Nickel(II) dibromide were increased with increasing of the monomer pressure from 1 up to 6 bar which studied. Explicitly, the ortho-substituent has a significant effect on the catalyst behavior. Melting point and crystallinity of the obtained polyethylene using 1,2-bis(2,4,6-trimethyl phenyl imino) acenaphthene Nickel(II) dibromide catalyst were increased with enhancing monomer pressure. The optimum and stable structures were computed and some factors related to the activity were studied. Catalyst 1,2-bis(2,4,6-trimethyl phenyl imino) acenaphthene Nickel(II) dibromide had the highest activity with the highest quantities of dipole moment (18.29 Debye), charge of Mullikan on metal atom (1.48) and Sum of electronic and thermal Energies (–7906.52 e.u.). 相似文献
748.
Abolghasem Farhadipour Hossein Eshghi Mohammad Hassan Alizadeh Mozhde Yousefi Beñat Artetxe Juan M. Gutiérrez-Zorrilla 《Journal of the Iranian Chemical Society》2016,13(6):1133-1138
Two new Melamine-Keggin hybrid nanorods, MELH-PMo12 and MELH-PW12, for the first time are successfully synthesized by two chemical methods, one-step solid-state chemical reaction method and experimental solvent diffusion method at room temperature. One-step solid-state reactions involve grounded nanorod materials along with grinding of row material and with solvent diffusion method these nanorods synthesized in single crystals form. These compounds crystallized in trigonal space groups P-3. Elemental analysis, infrared spectroscopy, UV spectroscopy and XRD analysis results prove that the samples still possess Keggin type structure. Transmittance electron microscopy and single-crystal X-ray have shown that the samples have nanorod structures. 相似文献
749.
Hossein Akhlaghi Mahdi Ghorbani Nahid Afshar Lahoori Alireza Shams Orkideh Seyedin 《Journal of Analytical Chemistry》2016,71(7):641-647
A simple, sensitive and selective solid phase microextraction with hollow fiber-supported multi-walled carbon nanotube functionalization reinforced sol–gel combined HPLC method was proposed for the determination of naproxen in tap, well and river water samples. In this method, functionalized multi-walled carbon nanotubes (MWCNTs) were prepared and held in pores of hollow fiber with sol–gel technology by immersion of polypropylene hollow fiber segment into the sol of the functionalized MWCNTs/silica composite and ultrasonically treated at room temperature. Effect of main parameters such as volume of donor phase, pH, extraction time, desorption time, type of desorption solvent, sample ionic strength and stirring rate were studied. Under optimum conditions, linearity was observed in the range of 0.03–500 ng/mL, with correlation coefficients of 0.997. The relative standard deviation for three replicate determinations of 50 ng/mL of naproxen was 4.3%. Limit of detection and pre-concentration factor were 0.008 ng/mL and 198, respectively. In order to check the applicability of the proposed method, it was used to determine trace levels of naproxen in different water samples. 相似文献
750.
Mozaffar?AsadiEmail author Khosrow?Aein?Jamshid Ali?Hossein?Kyanfar 《Transition Metal Chemistry》2007,32(6):822-827
A u.v.–vis spectrophotometric study of the adduct formation of the nickel(II) Schiff base complexes,([NiL]) where L = [3-methoxysalophen,
N,N′-bis(3-methoxysalicylidene)-1,2-phenylenediimine] (1), [4-methoxysalophen, N,N′-bis(4-methoxysalicylidene)-1,2-phenylenediimine] (2), [5-methoxysalophen, N,N′-bis(5-methoxysalicylidene)-1,2-phenylenediimine] (3) and [Salophen, [N,N′-bis(salicylaldehydo)-1,2-phenylenediimine] (4) as donors with R2SnCl2 (R = methyl, phenyl and n-butyl) as acceptors have been investigated in chloroform, as solvent. Adducts have been characterized by 1H, 13C and 119Sn NMR, IR and electronic spectroscopy and CHN elemental microanalysis. The formation constants and the thermodynamic free
energies were measured using u.v.–vis spectrophotometry titration for 1:1 adduct formation at various temperatures (T = 278
to 308 K). The trend of the adduct formation of the nickel Schiff base complexes with a given tin acceptor decreases as follows:
and
The trend of the reaction of R2SnCl2 acceptors toward a given nickel Schiff base complex is as follows:
相似文献